Energy tourism in Serbia: online representation of the hydro energy tourism

: Energy tourism is an emerging type of tourism that received increasing attention in the recent period. Hydro plants were part of the energy tourism offer that has been attracting the tourist throughout the time. Thus, revealing the online representation of their textual and visual content is of considerable interest for countries that aim to enhance this specific tourism activity. Serbia has an unfavou rable structure of exploited energy sources with a significant share of renewable source , in contrast to considerable hydro energy potential, both for energy creation and tourism usage. By acknow ledging the current state of the tourism use of hydro plants, understanding its attraction and experience value, and future activities that could derive from it is an initial step in formulating tourism management and marketing efforts.


Introduction
Nowadays, tourists are driven by unique and novel experiences. Thus, 'energy regions' [1] have become a novel tourism product that has the capacity to attract the considerable interest of the contemporary tourist. Population inhabited outside energy landscapes is not fully aware of the aesthetic, educational, experiential, spatial and environmental aspects of 'energy regions' in the tourism context [2], so visitation of these regions should generate substantial interest. Energy-tourism encircles various tourist initiatives: educational trails, exhibitions, guided tours to energy camps [3]. Finally, 'energy tourism has considerable societal relevance [3], especially regarding clean energy solutions, climate change and sustainability in general.
Energy tourism can be regarded as a segment of special interest tourism [4] and/or industrial tourism segment [5]. Energy tourism "involves visits by tourists to former, retired, or regenerated sites, as well as to still operational energy sites where some facilities, services, or activities have been provided specifically for tourists' use" [6, p. 1398]. According to Frantál & Urbánková [6] energy-tourism nexus conceptualization, the following three perspectives were highlighted: energy as a driver of tourism, energy as a constraint of tourism and energy as a tourist attraction. Jiricka et al. [3] proposed two approaches towards the creation of the energy tourism product. The first one is expert-based energy-tourism, while the second relies on energy experience tourism.
Some previous studies [7,8,9] were focused on the nexus between energy and tourism, emphasizing the relationship between tourism turnover and energy consumption. Conversely, some recent studies [3,8,10] have initiated the energy tourism discussion that nurtures the value of energy tourism attractions and their visitation's experiential dimension. Thus, the proposed study follows the attraction/experience-based trend and investigates Serbia's underinvestigated energy tourism product.
The shift within energy tourism research was also made from traditional energy sources towards exploiting renewable energies in a tourism context [11]. First attempts at examining renewable energies as a niche tourism product have been made by Jiricka et al. [3]. Frantál & Urbánková [6] study of energy tourism has acknowledged both renewable and traditional energy sources as energy tourism examples. However, hydro energy and plants as the first known electric energy source have unfortunately not received well-deserved attention. Thus, the proposed study will further examine the phenomena by depicting the value and experience embedded in a hydro-plant facility and its tourism visitation.
Previous studies [3,6] have implemented demand and supply evaluation of the specific energy tourism sites, however, there is still limited understanding of their online representation, especially in the context of the (hydro) energy tourism supply. Thus, it was interesting to systematize and analyze the current tourism offer regarding Serbia's hydro energy, especially how this offer was textually and visually presented to the potential visitors.
Thus, the paper aims to identify and analyze the online content related to hydro energy tourism attractions and accompanying experiences in Serbia. In this way, the existing Serbia hydro energy tourism offer was systemized, leading to the enhancement of its visitations in the future. The contribution of the study was both theoretical and practical. Theoretically, energy tourism as a niche topic benefits the novel approaches, while practically it raises the awareness of its existence and importance of renewable sources for achieving sustainability.

Materials and methods
Serbia has a long history of hydro energy use. For example, hydro plant "Pod Gradom" was the first hydro plant in Serbia and, among the first ones in Europe, initially set in motion in 1900, solely four years after launching the Niagara Falls power plant. "Pod Gradom" was built following Nikola Tesla's patents and inventions introduced by his close friend and collaborator professor Đorđe Stanojevic. Electrification of Serbia using hydro energy continued with the following hydro-power plants, such as Vucje built in 1903, Sveta Petka in 1908, Gamzigrad in 1909, Moravica in 1911, Temac in 1940, etc.
Serbia's current energy policy is based predominantly on traditional energy sources (see Table 1). Thus, giving proper attention to its hydro energy potential and its valorisation as a tourism resource would strengthen an initiative of restructuring the current energy policy towards renewable energy sources, with particular attention given to hydro energy. A two-step content analysis approach was employed to propose a comprehensive understanding of Serbia hydro energy tourism's online representation. The first step includes mapping a pool of sampled Serbia hydro energy tourist attractions (hydro-plants) and accompanying experiences and showing their visibility on Google. The second step encircles analysing online content of previously singled attractions and their accompanying experiences. In the first step, to identify Serbia's hydro energy tourism potential and chose the appropriate keywords for Google search, an examination of hydro energy tourism attractions (larger and smaller hydro plants) was deployed. Thus, to identify larger hydro plants names, the online energy portal was used [12], while small hydro-plants names were chosen based on the map proposed on elektroenergetika website [13]. As a final Google query, names of identified larger and smaller hydro plants were combined with the keyword "hydro plant energy tourism".
An index called "visibility ratio" [14] was calculated by dividing the number of results presented by the total number of Web pages indexed by Google containing the hydro-plant name. Only the first ten webpages retrieved through Google search based on the hydro energy tourism search were further analyzed regarding its content. The websites were analyzed to identify a direct resemblance to energy tourism, following the identified websites' content. A combined approach focus on both attractions [6] and accompanying experiences [3] was deployed.

Results and discussions
Initially, Serbia energy tourism and a more focused search term Serbia hydro plant energy tourism were examined within the Google trends search (both globally and on a national level), however, it has not generated enough data to implement analytics. Thus, a manual search was implemented in line with the methodology proposed by Xiang et al. [14].
Overall, 45,735,430 Web pages are related to 36 hydro-plants (11 large and 25 smaller) as hydro energy tourist attractions. However, only a very small fraction of indexed Web pages are shown as search results (mean=696 Web pages) accessible to a user (490.163), resulting in an overall visibility ratio of 0.010%. Considering that most engine users only view the first search result page, the actual visibility ratio is much lower. Djerdap hydroplant, as an internationally renowned and largest hydro plant on the Danube in Europe, have a high visibility ratio of 0.113. Interestingly, some of the hydro plants that were small and not of such importance had indicated visibility ratios that are higher in comparison to Djerdap hydro plant, for example, it has been noted for Sicevo (0.705), Vucje (0.102) and Temac (0.264) small hydro plants (see Table 2). Within the second phase of the research, each of the hydro tourism attraction and websites on its first search page has been individually examined regarding the online content. Based on the gathered data of large hydro plants presented in the previous table, the following conclusions should be made: Only one sizeable hydro plant (Djerdap) (Figure 1) provide some reference to an organized tour of its facilities, however, only as a part of the tour package provided by a travel agency and not specifying details of what kind of experience they offer.  [16].

Departure to Đerdap HE plant and a tour of one of the largest HE plants in Europe
The Perucac artificial lake has been extensively visualized, however, solely one photo of the Bajina Basta hydro plant was proposed.

Uvac
http://www.serbia.com/visit-serbia/naturalbeauties/unique-nature/uvac-a-natures-masterpiece/ https://www.republiktours.com/explore/uvac-lake/ https://balkangreenenergynews.com/eps-gets-approvalin-serbia-for-gornja-drina-hydropower-project-in-bih/ In contrast to larger hydro plants that have been interpreted within a broader tourism context, the smaller hydro plants were generally tourism-focused and widely discussed as tourism attractions within the analyzed website content. Several of the smaller hydro plants (Pod Gradom, Sveta Petka and Vucje) were attracted the interest of ERIH (European Route of Industrial Heritage) as they act as anchor points under the patronage of ERIH (Figure 2).  Table 4).

Conclusions
Based on the Google web pages analysis, Serbia's hydro energy tourism attraction's overall visibility is relatively low, especially since most of the identified and analysed web pages (within the analysed first ten) is not related to the keyword search. Moreover, a large number of searches was limited only to one search result page.
The textual and visual online representation of the Serbian hydro energy tourism offer was grounded on a combined expert and experience-based energy tourism approach [3]. An expert-based approach could be referred to hydro plant "Pod Gradom" visitation as a part of the social programme within the International conference on power plants. Analysis of the online content has recognized an initial effort to create hydro plant experiences, both as a 'stand-alone' offer or tour packages (especially those within the ERIH route and Tesla Ways). Unfortunately, this offer has a limited correlation with the 'traditional tourism offers', thus, additional effort should be invested in complementing artificial lake activities formed by larger hydro plants with the hydro plant experience itself. Thus, this issue deserves additional attention, especially considering future tourism management and marketing efforts.
Visual content follows abundant textual material identified within the small hydro plants' content analysis. The particular interest was given to the smaller hydro plants' architecture and technology in line with their importance of industrial heritage guardians acknowledged by ERIH and the Tesla Ways route. The majority of analyzed small hydro plants examples were driven by the value and uniqueness of its technical facilities, which are opened to the public via guided tours. Thus, the analyzed offer is predominately driven by its industrial heritage and educational purposes that derive from it. It is in line with the Kolblmüller and Bärntaler [17] argument that knowledge transfer (technological facts and benefits discussed during guided tours or seminars) was an essential element of energy-tourism. To some degree (primarily for small hydro plants), environmental education and raising environmental awareness were pointed out, which could direct awareness towards renewable energies, especially considering Serbia's energy structure and its comparison to EU countries. Unfortunately, other tourist experiences that derive from the hydro plant visitation are neglected.
Finally, looking from a perspective of the scale of the facilities, surprising results were obtained. One could expect that larger hydro plants will dominate the offer, however, except Djerdap HE, other larger hydro plants were not considered as tourist attractions per se, yet only in the context of their dams and accompanying artificial lakes and experiences that derive from it. Thus, it could be concluded that based on the current online representation, their value was recognized only as a part of broader natural scenery. Moreover, analysis of Djerdap hydro plant energy tourism web pages, regardless of its continental importance, has limited reference to tourism, especially regarding opportunities of its visitation and proposed experiences. The main reason behind that acquired findings is that these facilities are considered essential energy suppliers in public property, so their visitation is strictly forbidden as a strategic national importance resource.
The study was also faced with several limitations. Analysis of the Google search results reflect the specific point in time, and thus it is challenging to make generalizable conclusions based on these findings. The study was also faced with the limited material written in English, the issue expected for the initial phase of the energy-tourism development and its perception on a national scale. Thus, future research endeavours should be directed in evaluating the existing online offer on the Serbian language, as it will provide a more realistic insight into the investigated phenomena.